Method of and means for generating mechanical elements



' H.'J. SCHMICK. METHOD OF AND MEANS FOR GENERATING MECHANICAL ELEMENTS.

APPLICATION FILED DEC-11.1919

Patnted 0 a 4, 1921.

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IEIIIIIIII IIIIIIUIIIIEDIIIIBI'IIIIIIIIIIIIIIII'INIIIIIIIIIIE attomwqr H. J. SCHMICK.

METHOD OF AND MEANS FOR GENERATING MEGHANICAL ELEMENTS.

' APPLICATION FILED 050.11, 1919.

' 1,392,528, Patented Oct. 4, 1921.

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I awvawtoz Wiimooo 6/9727? J H. J. SCHMICK. METHOD OF'AND MEANS FOR' GENERATING MECHANICAL ELEMENTS.

APPLICATION FILED DEC. H, I9l9- Patented 00a 4',""1921.

3 SHEETS-SHEET a.

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UVNITED STATES PAT T OFFICE.

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SCREW AND GEAR COMPANY, or WILMINGTON, DELAWARE, A coRroRA'rIoN or DE AWA E METHOD OF AND To all whbm-z'tmay concern Beit known thatrI, HENRY J. ScHMIOK, a citizen of the United States, residing at 'VVilliamsport, in the county of Lycoming and State of Pennsylvania, have invented certain new and useful Improvements in Methods of and Means for Generating Mechanical Elements, of which the following is a specification.

stantially at right angles to the axisof the blank,-and so related as ,fb merge on nonradial lines'to produce a working face or faces of particular t pe, to thereby materially increase the, e ciency of the element produced aS compared with the present type of similar element. Y

. The preferred mode ofpractising the invention contemplates; providing apparatus wherein the blank is so directed and con- '1 trolled and the cooperating cutter so related to the blank, that in operation the desired formation of element will necessarily result.

In the drawings Figure l is a view in elevation of a simple typeof a suitable machine for practising the invention;

Fig. 2 is aplan view of the same; Fig. 3 is a section on the line 3-3 in Fig. 1, looking in the direction of the arrows,

' showing the mounting of the blank;

Fig. 4 is a side elevation of a continuous feed type of machine constructed: in accordance with the present invention;

5 is a longitudinal section of the same; 7 I I Fig. 6 is a" transverse section of the same on the line 66 in Fig. 4;

Fig. 7 is a transverse section similar to Fig. 6 of-a modified form of machinehavinga single cutter.

ig. 8is adiagrammatic view illustrative of a generating Ope ation for a W Figis a d agrammat c v ew s ra i of: the gen r ting: mpvement cutter, a shown in Fig; 1; .1

PENNSYLVANIA, AssIeNoR' 'ro soI rIIoK MEANS FOR GENERATING IIEoEAN'IoAL ELEMENTS. V

Specification bf Letters Patent. P te t d Oct.- 4, 1921. Application filed December 11, 1919. Serial No. 344,265. Y V v Fig. 10 isa diagrammatic view illustrative of a generating movement of a cutter as shown in Fig.4; and 7 A Fig. 11 is a view of the partially com pleted blank made by operation of the machine of'Fig. 1.

The invention 1s here shown embodied in machines 1 for the generation of screw,

threads, but it is to be understood that thel' principle involved is equally, applicable to the generation of other elements of similar character. i

In Figs. 1, 2;, and 3, a simple singlecutter type of machine is illustrated, comprisingv a frame 1 similar toathatof a lathe having the ordmaryidriven head stock2, and itail stock 3. The feed screw 4 for'the traveling cutter headsupport or*block 5 is driven by gears from the head stock in the usual or any desired way, and the cutter head 6. is adjustable lengthwise and crosswise on said block as usual. i i v For the performance of the present inven tion .in this type ofmachine, it is desirable to give the blank an eccentric movement rela- I tive to the cutter 7, and. forthispurpose the-blank-S is mounted on a spindle having.

disk .heads 9 and 10. The disks are formed with a concentric seriesof openings 11, hereinafter termed centers, arranged near. .the peripheral edges of the disks. These centers provide a series of centers of rotation of the blank, and are to successively engage with the head and tail stock center pins, as shown diagramatically in Fig. 9. The head stock carries'a face plate or disk 12, having. near its peripheral edge a pin or. otherv suitable engaging member 13:,- adapted to enter an appropriate notch inithe adjacent spindle disk 9, to thereby fix the disk against inde pendent movement and insure the eccentric;

rotation of the blank 8.

In this type of machine, as will be plain from Fig. 9, the cutter maybe adjustedto suit the blank and is maintained throughout the operation at the same angle, preferably 1 a direct right angle to the'axis of the blank.

When the blank is rotated it is given an eccentric movement relative to its axis to bring a single segment into engagement with the cutter in each turn of the lathe. Of course itis understood-that following each cutting engagement the cutter 1 1-, if held fixed during the putting p rati n, isin ex d menu:-

ally to offset the next segmental cut axially with reference to the preceding out. If the 'cutteris fed by the screw, as shown in. Figs.

1, 2 and 3, each revolution of the blank will produce a similar segmental cut or eccentric formation. at successive predetermined points in the feed of the screw, and following each of which cuts the lathe is stopped and the blank given a new relative position by causing the lathe centersto engage in the next pair of alining blank centersll. If

the cutter is held stationary instead of being 7 fed by thelead screw it is manually indexed between each cut to ive the lead or offset to the next eccentric ormation, and the op-. eration is thus continued. Fig. 11 illustrates the artially complete blank produced by a mac ine similar to that shown in Figs. 1, 2

and 3,and will be later described in more.

detail.

In Figs. 4 to 7 inclusive is shown a con-' tinuously operating machine having a plu-' rality of cutters, and this is a preferred type of machine. In this type,th e headand tail stocks l5and 16, are in the form of internal gear members, having also external driving gears 17, adapted to be engaged and'operated by Finions 18 on a. sha

are provided with fixed pinions' 21, and the blank 22 is supported in end members 23, formed as pinions held between the rotating.

internal gears'16 and 15 and the pinions 21. In this type the cutter maybe a single cut- .ter as shown in Fig. 7' or'preferablymade up in a series, 24, mounted in a ring 25, surrounding the path of travel of the blank, and slidably mounted on the bed. 'The ring engages with a feed screw 26, driven through gears 27,. wherebythe cutter ring may be. properly fed. f

The cutters are preferably" mounted for radial adJuStment in the ring, so as to provide for increased cutting depth as the work proceeds; and for this. purpose, the cutters are made in four sections as shown in Fig.

19, and are fed inwardly or outwardly ra-. dlally of the ring by a positioning cam mem ber 28, operated at will through gear connections 29, controlled by a hand operated turning member 30. In this form of structure, the eccentric 'movement of the blank relative to the cutter is carried out, exactly as in the preferred form, as is clearly apparent in Fig. 10.

Assuming now the successive cuts or eccentric formations, each slightly offset in the dlrection of travel, and each substantially.

at right angles to the axis, it becomes at once apparent that to produce a continuous thread or other, element there must be a sufficiently close spacing of thecuts to effect the merger of their remaining portions. It is believed that this will be particularly apparent from Fig. 11 of the drawings. The

ower shaft 119. The t supports 20 of t e head and tail stocks lines indicated at 31 clearly show the successive eccentric formations resulting from the closely spaced cuts,and it is apparent that from the successive axial offsetting of the spaced eccentric formations, remaining and from the further factthat each one is,

at substantially a direct right angle to the axis of the, blank, it results that the bottom of one formation gradually merges in the side of" a succeeding formation, until the bottom line of one eccentric formation may finally become the top of a succeeding formation. This merging ismost clearly seen in Fig. 11, wherein the formation'is not fully completed. Here it is apparent that one sidcof a cut or formation, as 32, is directly an extension of the opposite side-'33 of a former formationl Ofcourse these fOrmation's' mergefinally into a thread like forma tion having any pitch desired; but this does not" change the relative disposition of the operating faces, and the resultant formation comprises a continual crossing of its line of direction by the successive cuts, as indicated by the facesf32 and 33 of Fig. "-11 and a continually advancing series of linesof in tersection or merger of their respective faces.

with the top and thebottom'of successive:

formations.- V

In Fig. 8, the same principle of eccentric generation'is applied to the formation of a worm. The blank-36, exteriorly 'shaped, is' mounted for the eccentric movement de-- scribed, on disks- 37 ,38, and cut by a gear cutter 39, indexed by means 40. The cutter is or may be generated initially by the present method, and then used to form the'worm.

Havingthus described the invention,what

is claimed as new is 1. A method of generating mechanical power transmitting'elements of thecontinuously rotating type, consistinginrotating the blank element upon its ax s and swinging it through a path eccentric to'the cutter, and

uniformly changing the. relative positions of said blank element and cutter while main tainingthe cutter-at the successive cutting points substantially at right anglesto the character described from a suitable blank by a series of segmental cuts taken transversely of the axis of" the blank and spaced axially and circumferentiallyto[form a groove of greater pitch than the angle made by said cuts with'a planeat right angles to the axis. 1

'ters, a blank support 4. A mechanical element generating machine comprising head and'tail stocks, and means for supporting a blank relative to such stocks so as to travel in a path eccentric to itself.

5. A generating machine comprising cenhaving a plurality of centers concentric with the blank and adapted to be successively engaged with the machine centers, and a cutter held at right angles to the axis of rotation of the blank.

6. A generating machine including rotating means for supporting a erated upon and means for successively changing the center of rotation of the blank supporting means, a cutter held at right angles to the blank and intercepting the ath of travel of the blank at one point t erein, and means for imparting a relative indexing movement to the cutter and blank between cuts whereby successive cuts are displaced circumferentially and axially with reference to one another.

7. Apparatus for producing articles of blank to be opthe character described comprising means for mounting a suitable blank for rotation about a center eccentric to its axis, means for holding a suitable cutter in position to engage a portion of the periphery of said blank and cut a segment therefrom, and means for displacing said cutter and blank axially and circumferentially between successive cuts whereby they merge to form a winding groove.

8. Apparatus for producing articles of the character described comprising means for mounting a suitable blank for rotation about a center eccentric to its axis, means for holding a suitable cutter in position to engage a portion of the periphery of said blank and cut a segment therefrom, means for shifting the center of rotation and maintaining the eccentricity of saidblank, and

means for displacing said cutter and blank axially between successive cuts whereby they merge to form a winding groove.

In testimony whereof,I affix my signature.

HENRY J SCHMICK. 

